Spring tension relieving device for negative dobby

Abstract

A drawing device for actuating the heddle frames of a weaving machine of the negative type including rocking levers which guide cables extending from the heddle frame to a return spring system. The rocking levers are mounted on shafts which are shiftable within elongated slots to thereby relax tension on the cables and spring system.

What is claimed is: 
     
       1. In a weaving machine including a drawing device for actuation of heddle frames of weaving mechanisms of the negative type which includes for each frame at least one control cable which extends from the frame over a lever mounted to oscillate on a support shaft carried by fixed structures of the weaving mechanism to a spring system which is normally under tension, the improvement comprising, the support shaft being guided inside spaced guide slots, adjustment means extending into said guide slots, said support shaft being displaceable along said guide slots by said adjustment means to thereby release tension on the spring systems. 
     
     
       2. The combination of claim 1 in which said guide slots have upper and lower ends, said guide slots being inclined outwardly relative to the heddle frame from said upper toward said lower end thereof, whereby as said adjustment means displaces the support shaft toward said lower ends of said guide slots, the cable will be shifted away from the heddle frames. 
     
     
       3. The combination of claim 2 in which said guide slots are provided in flanges mounted to the fixed structures, first openings in each of said flanges and second openings in the support shaft, and a threaded fastener extending through said first openings in said flanges and into said second openings in the support shaft. 
     
     
       4. The combination of claim 1 in which said guide slots are provided in flanges mounted to the fixed structures, first openings in each of said flanges and second openings in the support shaft, and a threaded fastener extending through said first openings in said flanges and into said second openings in the support shaft. 
     
     
       5. The combination of claim 1 in which said spaced guide slots are generally triangular in configuration having upper and lower portions, said lower portions having first and second adjacent recesses formed therein in which the support shaft is selectively seated. 
     
     
       6. The combination of claim 5 wherein said second recesses are spaced outwardly at a greater distance from the heddle frame than said first recesses. 
     
     
       7. The combination of claim 6 in which said guide slots are provided in flanges mounted to the fixed structures, first openings in each of said flanges and second openings in the support shaft, and a threaded fastener extending through said first openings in said flanges and into said second openings in the support shaft. 
     
     
       8. In a weaving machine including a drawing device for actuation of heddle frames of weaving mechanisms of the negative type which include for each frame a spring system which is normally under tension and means for connecting the spring system to the frame and wherein the means for connecting the spring system includes a rocking lever mounted to a support shaft carried by fixed structures of the weaving machine, the improvement comprising, the support shaft being guided inside spaced guide slots formed within said fixed structures, adjustment means extending into said guide slots, the support shaft being displaceable along said guide slots by said adjustment means to thereby release tension on the spring system. 
     
     
       9. The combination of claim 8 in which said guide slots have upper and lower ends, said guide slots being inclined outwardly relative to the heddle frame from said lower toward said upper end thereof.